An accumulating conveyor comprises a conveyor belt successively follows a first helical track from a lower end thereof in upward direction to a location below an upper end thereof, a first bridge to a location at a second helical track below an upper end thereof, the second helical track in downward direction to a lower end thereof, a first set of auxiliary guides to the upper end of the second helical track, the second helical track in downward direction, a second bridge to the first helical track, the first helical track in upward direction to the upper end thereof, and the second set of auxiliary guides to the lower end of the first helical track. The bridges are synchronously movable along the first and second helical tracks for varying the effective lengths of the conveyor belt.

A heat transfer system includes a conveyor belt having air permeable outer and inner side walls and forming a conveyor stack having a plurality of tiers and a central space with a volume. A first portion of the volume and a first plurality of tiers are in a first sub-chamber and a second portion of the volume and a second plurality of tiers are in a second sub-chamber. The system further includes generating means which: produces, in the second sub-chamber, airflow in a horizontal direction towards the conveyor stack and in a horizontal and radial direction across the second plurality of tiers to enter the second portion of the volume; and draws, in the first sub-chamber, the airflow in a horizontal direction away from the conveyor stack and in a horizontal and radial direction to exit the first portion of the volume across the first plurality of tiers.

A spiral conveyor for positively driving a conveyor belt along a helical path. The spiral conveyor includes a rotating cylindrical tower with parallel drive members extending from the bottom to the top of the tower on its periphery. Each drive member includes an outwardly protruding ridge that varies in height from the bottom to the top of the tower. The variations in height facilitate the belt's entry onto and exit from the tower and robust, positive driving engagement with the inside edge of the belt along the majority of its path along the tower.

A spiral conveyor for positively driving a conveyor belt along a helical path. The spiral conveyor includes a rotating cylindrical tower with parallel drive members extending from the bottom to the top of the tower on its periphery. Each drive member includes an outwardly protruding ridge that varies in height from the bottom to the top of the tower. The variations in height facilitate the belt's entry onto and exit from the tower and robust, positive driving engagement with the inside edge of the belt along the majority of its path along the tower.

A rail and track cartridge for building straight or radial belt conveyors comprises two or more rails connected to each other, wherein the two or more rails each has a first and second free end; and a track connected to each rail, wherein each track is supported by tabs protruding from the rail, wherein the track is offset to the side from the rail, and an upper track surface is above a top surface of the rail. An adjustable cartridge has bent free ends of the two or more rails attached to the same tier arm to adjust the length of the rails to fit within the tier arms.

A rail and track cartridge for building straight or radial belt conveyors comprises two or more rails connected to each other, wherein the two or more rails each has a first and second free end; and a track connected to each rail, wherein each track is supported by tabs protruding from the rail, wherein the track is offset to the side from the rail, and an upper track surface is above a top surface of the rail. An adjustable cartridge has bent free ends of the two or more rails attached to the same tier arm to adjust the length of the rails to fit within the tier arms.

A spiral conveyor for positively driving a conveyor belt along a helical path. The spiral conveyor includes a rotating cylindrical tower with parallel drive members extending from the bottom to the top of the tower on its periphery. Each drive member includes an outwardly protruding ridge that varies in height from the bottom to the top of the tower. The variations in height facilitate the belt's entry onto and exit from the tower and robust, positive driving engagement with the inside edge of the belt along the majority of its path along the tower.

A spiral conveyor for positively driving a conveyor belt along a helical path. The spiral conveyor includes a rotating cylindrical tower with parallel drive members extending from the bottom to the top of the tower on its periphery. Each drive member includes an outwardly protruding ridge that varies in height from the bottom to the top of the tower. The variations in height facilitate the belt's entry onto and exit from the tower and robust, positive driving engagement with the inside edge of the belt along the majority of its path along the tower.

A spiral conveyor having a self-stacking conveyor belt positively driven on a helical path up or down a drive drum. Stacker supports at opposite sides of the belt support the tiers above. Locking structure on the outer stacker supports interlock consecutive tiers. Drive members on the drive drum have a belt entrance segment and a positive-drive segment. The positive-drive segment has ridges that engage the inner side of the belt without slip. The entrance segment provides a smooth reduction in drum diameter without drive ridges to multiple belt tiers entering the helical path.

A spiral conveyor having a self-stacking conveyor belt positively driven on a helical path up or down a drive drum. Stacker supports at opposite sides of the belt support the tiers above. Locking structure on the outer stacker supports interlock consecutive tiers. Drive members on the drive drum have a belt entrance segment and a positive-drive segment. The positive-drive segment has ridges that engage the inner side of the belt without slip. The entrance segment provides a smooth reduction in drum diameter without drive ridges to multiple belt tiers entering the helical path.